The assignee of the present invention manufactures and deploys spacecraft for, inter alia, communications and broadcast services. Market demands for such spacecraft have imposed increasingly stringent requirements on spacecraft payloads. For example, broadband service providers desire spacecraft with increased data rate capacity at higher EIRP through each of an increased number of user spot beans. To meet the more stringent demands, a high power (20 KW+) spacecraft capable of providing at least 200 Gbps total data bandwidth distributed across at least one hundred spot beams is desirable. A spacecraft configuration appropriate to such a demand may be required to accommodate several antenna reflectors, each having a diameter of three to five meters. Because preferred antenna optics have a ratio of focal length (f) to antenna diameter (d) of two or greater a focal length of six to ten meters should be accommodated.
Launch vehicle compatibility is a second requirement faced by a spacecraft designer. The increased performance requirements are only advantageously met if compatibility with conventional, commercially available launch vehicles is maintained. This means, for example, that a spacecraft, as configured for launch, should be maintained within a mass and fairing envelope compatible with multiple launch vehicles, including, for example, Ariane V, Atlas XEPF, Proton, and Sea Launch.
Thus, there is a need for a high power broadband spacecraft, having multiple large antenna reflectors with long focal lengths, that is compatible with such conventional launch vehicle constraints.